package com.hmdp.utils;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.util.StrUtil;
import com.hmdp.dto.UserDTO;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Map;
import java.util.concurrent.TimeUnit;

@Component
public class RefreshTokenInterceptor implements HandlerInterceptor {


    //因为拦截器是单例模式，不能使用autowired或resource注解，只能使用钩子函数注入
    //stingRedisTemplate 这个类的对象是我们自己定义，new出来的，不是由spring管理的
    private StringRedisTemplate stringRedisTemplate;

    public RefreshTokenInterceptor(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        // 1. 获取请求头中的token
        String token = request.getHeader("authorization");
        if (StrUtil.isBlank(token)) {
            return true;
        }

        //2.基于token获取redis中的用户信息
        String key = RedisConstants.LOGIN_USER_KEY + token;
        Map<Object, Object> userMap = stringRedisTemplate.opsForHash()
                .entries(key);
        //3.判断用户是否存在，
        if (userMap.isEmpty()){
            //直接放行
            return true;
        }
        //将查询到的HashMap转换为UserDTO对象
        UserDTO userDTO = BeanUtil.fillBeanWithMap(userMap, new UserDTO(), false);
        //5.存在，保存用户信息到ThreadLocal中
        UserHolder.saveUser(userDTO);
        //刷新token的过期时间
        stringRedisTemplate.expire(key,RedisConstants.LOGIN_USER_TTL, TimeUnit.MINUTES);
        //6.放行
        return true;
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        //清理ThreadLocal 中的用户信息
        UserHolder.removeUser();
    }
}
